1. Field of the Invention
The present invention relates to a wiring harness arranged in a mobile unit such as a motor vehicle and also relates to a manufacturing method of the wiring harness.
2. Related Art
A motor vehicle has a wiring harness for supplying power to electrical appliances, such as various lamps and motors, from a battery. A conventional wiring harness includes a plurality of electrical cables, a plurality of terminals each fitted to an end of each electrical cable, connector housings accommodating the terminals, and a connection portion. The electrical cable is an insulated cable having a wire core and an insulating cover.
The connection portion electrically connects the electrical cables to one another. The connection portion directly connects the wire cores of some of the electrical cables to one another.
For example, the connection portion connects one end of the wire core of one electrical cable to one end or a longitudinal middle of the core of another electrical cable. The connection portion connects the wire cores to each other by press-crimping them with a joint terminal or by hot-press-crimping of a resistance welding device.
To obtain the conventional wiring harness, a terminal is fitted to an end of an electrical cable by press-crimping or press-fitting, for example, in the use of a press-fitting unit disclosed in Japanese Patent Application Laid-open No. H. 10-154568 or a press-crimping unit disclosed in Japanese Patent Application Laid-open No. H. 9-115639.
For the connection portion, there has been used a press-crimping machine or a resistance welding device, for example, disclosed in Japanese Patent Application Laid-open No. H. 10-112229. Furthermore, a terminal is inserted into a terminal accommodation chamber of a connector housing to assemble a wiring harness with the use of an insertion device, for example, disclosed in the Application Laid-open No. H. 10-112229.
However, the conventional wiring harness needs to transfer the cables to the press-crimping machine or the resistance welding device for completing the connection portion. The transfer is disadvantageous for an automatic manufacturing method of the wiring harness.
That is, it requires a time and work steps for the transfer of the cables to the press-crimping machine or the resistance welding device and further to the insertion device. This causes a longer manufacturing time of the wiring harness.
Moreover, it also takes an increased time to align the electrical cables for press-crimping or heat-press-crimping them to one another by the press-crimping machine or the resistance welding device to complete the connection portion. Thereby, the conventional wiring harness requires a further increased assembling time, causing a lower productivity thereof.
In view of the disadvantages, an object of the present invention is to provide a wiring harness and a manufacturing method of the same, in which an improved productivity is allowed.
For achieving the object, a first aspect of the present invention is a wiring harness having a plurality of electrical cables and a connection portion electrically connecting one of the electrical cables to another of the electrical cables. The wiring harness includes:
a plurality of sub-harnesses each having at least one press-fit terminal and an isolator supporting the press-fit terminal, the press-fit terminal being joined to an end of one of the electrical cables, and
a connection means for connecting the press-fit terminals held by different ones of the isolators to ones another.
The connection portion is defined by the connection means that connects the press-fit terminals held by different ones of the isolators to one another when the isolators are layered.
A second aspect of the present invention is a wiring harness having a plurality of electrical cables and a connection portion electrically connecting one of the electrical cables to another of the electrical cables. The wiring harness includes:
a plurality of first sub-harnesses each having a first press-fit terminal joined to each end of a first one of the electrical cables, the first sub-harness having a first isolator holding the first press-fit terminal,
a plurality of second sub-harnesses each having a second press-fit terminal, a crimp terminal, and a connector housing for accommodating the crimp terminal, and a second isolator supporting the second press-fit terminal, the second press-fit terminal being connected to one end of a second one of the electrical cables, the crimp terminal being connected to the other end of the second electrical cable, and
a connection means for connecting the press-fit terminal held by one of the first or second isolators to the press-fit terminal held by another of the first or second isolators.
The connection portion is completed by the connection means that connects the press-fit terminals held by different ones of the isolators to one another when any of the first and second isolators are layered.
A third aspect of the present invention is a wiring harness having a plurality of electrical cables and a connection portion electrically connecting one of the electrical cables to another of the electrical cables. The wiring harness includes:
a plurality of first sub-harnesses each having a first press-fit terminal joined to each end of one of the electrical cables, the first sub-harness having a first isolator supporting the first press-fit terminal, and
a connection means for connecting one of the press-fit terminals held by one of the first isolators to the press-fit terminal held by another of the first isolators.
The connection portion is defined by the connection means that connects the press-fit terminals held by different ones of the isolators to one another when any of the isolators are layered.
A fourth aspect of the present invention is a wiring harness having a plurality of electrical cables and a connection portion electrically connecting one of the electrical cables to another of the electrical cables. The wiring harness includes:
a plurality of sub-harnesses each having a press-fit terminal, a crimp terminal, a connector housing for accommodating the crimp terminal, and a second isolator holding the press-fit terminal, the press-fit terminal being connected to an end of one of the electrical cables, the crimp terminal being connected to the other end of the one of the electrical cables, and
a connection means for connecting the press-fit terminal held by one of the isolators to the press-fit terminal held by another of the isolators.
The connection portion is defined by the connection means that connects the press-fit terminals held by different ones of the isolators to one another when the isolators are layered.
A fifth aspect of the present invention is a manufacturing method of a wiring harness having a plurality of first sub-harnesses, a plurality of second sub-harnesses, and a connection means. Each of the first sub-harnesses has a plurality of first electrical cables, a first press-fit terminal joined to each end of each of the first electrical cables, and a first isolator holding the first press-fit terminals. Each of the second sub-harnesses has a plurality of second electrical cables, a second press-fit terminal joined to one end of each of the second electrical cables, a crimp terminal joined to the other end of each of the second electrical cables, a connector housing receiving the crimp terminals, and a second isolator holding the second press-fit terminals. The connection means connects the press-fit terminals to one another when any of the first and second isolators are layered. The manufacturing method includes the steps of:
a first sub-harness assembling step,
a second sub-harness assembling step, and
a wiring harness assembling step, wherein any of the first and second isolators of the first and second sub-harnesses are layered, while the connection means connects the press-fit terminals held by different ones of the isolators to one another.
Preferably, the first sub-harness assembling step includes:
a first step for holding the first press-fit terminal by the first isolator,
a second step for cutting a long electrical cable to obtain the first electrical cable having a predetermined length, and
a third step for press-fitting the first press-fit terminal to each end of the first electrical cable.
Preferably, the second sub-harness assembling step includes:
a fourth step for holding the second press-fit terminal by the second isolator,
a fifth step for cutting a long electrical cable to obtain the second electrical cable having a predetermined length,
a sixth step for press-crimping the crimp terminal to the other end of the second the electrical cable,
a seventh step for press-fitting the second press-fit terminal to the one end of the second electrical cable, and
an eighth step for inserting the crimp terminal into a terminal accommodation chamber of the connector housing.
Preferably, the wire harness assembling step includes:
a ninth step for disposing any of the first and second isolators to be parallel to one another with a space therebetween, and
a tenth step for layering the parallel disposed isolators to connect the press-fit terminals held on different ones of the isolators to one another by the connection means.
In the first to fourth aspects of the present invention, the connection portion is defined by layering any of the isolators so that the press-fit terminals held by the different isolators are electrically connected to one another. Thus, the connection portion is defined without directly jointing the wire cores of the different electrical cables.
In the fifth aspect of the present invention, the wiring harness assembling step layers any of the first and second isolators to electrically connect the electrical cables to one another, which defines the connection portion. Thus, the connection portion is defined without directly jointing the wire cores of the different electrical cables.
In the first sub-harness assembling step and the second sub-harness assembling step, the wire cores of the electrical cables are not directly connected.
In the sixth aspect of the present invention, the third step fits the first press-fit terminal held by the first isolator to each end of the first the electrical cable to obtain the first sub-harness. In the first sub-harness assembling step, the wire cores of the electrical cables are not directly connected.
In the seventh aspect of the present invention, the second press-fit terminal held by the second isolator is fitted to the first end of the second electrical cable. The crimp terminal crimped to the second end of the second the electrical cable is inserted into the terminal accommodation chamber of the connector housing to obtain the second sub-harness. Thus, in the first sub-harness assembling step, the wire cores of the electrical cables are not directly connected.
In the eighth aspect of the present invention, the press-fit terminals held by the layered isolators are electrically connected to one another to complete the wiring harness. That is, the layering of the isolators connects the electrical cables to each other. Thus, the connection portion is defined without directly jointing the wire cores of the different electrical cables.
Next, advantageous effects of the present invention will be described.
In the aforementioned aspects of the invention, it is not required to directly connect the wire core of one of the electrical cables to that of another to define the connection portion. That is, the connection portion is defined without a press-crimping machine and a resistance welding device. Accordingly, the press-fit terminals need not be moved from main production lines of the sub-harness assembling to the press-crimping machine and the resistance welding device. This requires no increased production time, keeping a sufficient productivity.